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#include <bits/stdc++.h>
using namespace std;
long long n,i,li,a; 
int main() {
 cin>>n;
 for(i=0; i<n; i++)
  {
     cin>>a;
     if(a==1) li++;
  }
 if(li>=2) cout<<0<<endl;
 else cout<<2-li<<endl;
 cout<<2<<endl;
 cout<<1<<' '<<2;
 return 0; }